mariadb/libmysql
Monty 34eb10e406 MDEV-10138 Support for decimals up to 38 digits
Decimals with float, double and decimal now works the following way:

- DECIMAL_NOT_SPECIFIED is used when declaring DECIMALS without a firm number
  of decimals.  It's only used in asserts and my_decimal_int_part.
- FLOATING_POINT_DECIMALS (31) is used to mark that a FLOAT or DOUBLE
  was defined without decimals. This is regarded as a floating point value.
- Max decimals allowed for FLOAT and DOUBLE is FLOATING_POINT_DECIMALS-1
- Clients assumes that float and double with decimals >= NOT_FIXED_DEC are
  floating point values (no decimals)
- In the .frm decimals=FLOATING_POINT_DECIMALS are used to define
  floating point for float and double (31, like before)

To ensure compatibility with old clients we do:

- When storing float and double, we change NOT_FIXED_DEC to
  FLOATING_POINT_DECIMALS.
- When creating fields from .frm we change for float and double
  FLOATING_POINT_DEC to NOT_FIXED_DEC
- When sending definition for a float/decimal field without decimals
  to the client as part of a result set we convert NOT_FIXED_DEC to
  FLOATING_POINT_DECIMALS.
- variance() and std() has changed to limit the decimals to
  FLOATING_POINT_DECIMALS -1 to not get the double converted floating point.
  (This was to preserve compatiblity)
- FLOAT and DOUBLE still have 30 as max number of decimals.

Bugs fixed:

variance() printed more decimals than we support for double values.

New behaviour:
- Strings now have 38 decimals instead of 30 when converted to decimal
- CREATE ... SELECT with a decimal with > 30 decimals will create a column
  with a smaller range than before as we are trying to preserve the number of
  decimals.


Other changes
- We are now using the obsolete bit FIELDFLAG_LEFT_FULLSCREEN to specify
  decimals > 31
- NOT_FIXED_DEC is now declared in one place
- For clients, NOT_FIXED_DEC is always 31 (to ensure compatibility).
  On the server NOT_FIXED_DEC is DECIMAL_NOT_SPECIFIED (39)
- AUTO_SEC_PART_DIGITS is taken from DECIMAL_NOT_SPECIFIED
- DOUBLE conversion functions are now using DECIMAL_NOT_SPECIFIED instead of
  NOT_FIXED_DEC
2016-06-22 22:04:55 +03:00
..
client_settings.h MDEV-9117: Client Server capability negotiation for MariaDB specific functionality 2016-02-02 14:35:10 +01:00
CMakeLists.txt Merge branch '5.5' into 10.0 2015-06-11 20:20:35 +02:00
conf_to_src.c Bug#21973610: BUFFER OVERFLOW ISSUES 2015-11-06 16:41:55 +05:30
errmsg.c Fix a typo: use __attribute__(...) not __attribute(...) 2016-04-06 13:12:49 +03:00
get_password.c Cleanups: 2016-04-05 18:00:04 +03:00
libmysql.c MDEV-10138 Support for decimals up to 38 digits 2016-06-22 22:04:55 +03:00
libmysql.def Bug #12325444 : 60746: CLIENT_PLUGIN.H IS BROKEN 2011-04-06 17:31:26 +03:00
libmysql_versions.ld.in MDEV-5529 Sync libmysqlclient.so symbol versioning across distributions 2014-02-19 21:39:16 +01:00